The only snag, while shopping iTunes Store, you would like to perk up is that you may receive credit for those purchased tracks, of the similar album you are going for, in the form of a cut-down total album cost.

It is in the air, if you can believe Ina Fried CNET, a way out, which will allow you not to pay over again for the songs that you have purchased earlier from iTS, could be available to you.
If there is some weight in this news, you may expect it at Macworld '07 event in the month of January.
Via: tuaw.com